Calculator.



M. L. GLEARY.

CALCULATOR.

APPLICATION FILED JUNE 19, 1912.

2 SHEETS-SHEET 1.

Patented May 13,1913.

M. L. GLEARY.

CALCULATOR.

APPLIUATION FILED JUNE 19, 1912.

1,061,81 9. Patented'May 13, 1913.

2 SHEETS-SHEET 2.

Fig.5.

DIRECTIONS (a0 a to a month) aya Place starting day on inside dial, Opposite arrow in outside 1 dial. The No. opposite day desired orrtha outside dial, is the correct one. Example: Jan. 5 to Oct. 22: Place Jan. 5 opposite Arrow on outside dial; Opposite Oct. 22, is the No.

287, which is Q correcte To figure Exact No. of days, proceed as above ,and add one for every red, star passed and subtract two for the green star, except leap year, then subtract one. 8

' avwemtoz Wm 13., Cleazy Wituzooeo V new emu" r, or noise, mind.

catamaran. I ,0'1,81'9. a s t Patenteariay 1351919;

' v Application and m. it, 1131a has it. i'oacu.

. v l i I I v Toallwhoma'tmay concern. I Figure 1 is a face or to plan view of a.'. it known that I,.Msm') Lowni Cmsnr, referred embodiment of the inventi a citizen of the United States, residing at.

Boise, in the county of Ada and State ,of

Idaho, have invented certain new and useful mlproveme'nts in Calculators, of which the owing is a specification.

This inventionrelatesto calculators, and

particularly to devices for ascertaining the number of days which elapse between-any l two dates of the difierent months, by a simple manipulation of the parts of the device.

The invention has for its object to provide a device of .the above character, by, means of which eitherthe exact number of days which intervene between two different dates maybe computed, or by which the number of days, when reckoni thirty days to the month, may be comput as is often necessary in computing mterest.

Briefly stating, the invention com rises ,a' pair of dials, one concentric within t e other and the two dials rotatable with respect to, each other, one of the dials being divided into twelve sectors or spaces which represent successively the different months of the year, and .each; sector being divided into thirty equal subdivisions, the other dial, which in practice 'will be preferably stationary, being divided into 360 equal subdivisions, each one ofwhich is numbered. Certain indicia are provided onthe face of the rotatable dial to assist the operator in properly making the desired computation.

With such brief explanation of the essential parts of the invention, I will now state that an additional object ofthe in-' vention is to so construct the dials and subdivide them into the proper equal parts, so that the subdivision may be easily efi'ected, each dial having 360 subdivisions, and it being far easier to subdivide the dials into 360 equal parts than it would be to subdivide them into 365 parts. Theprovision' of the indicia before referred to, will render the computation of the exact number of days which elapse between any two specified dates an easy matter.

For a full understanding of the present invention, reference is to be had to the following description and to, the accompanying drawings, in which,

. vice, and Fig. 3 is a -seg'ment, which. is

ig. 2 is a vertical section'throu'gh the d'e fragmentary plan view} bringing out clearly the computing, indicia:

. and direc'tionsfor operating the calculator.

Throughout the following detail. descrip tlon and on the several figures of the draw-- reference characters. I V

' Referring particularly to the drawings,-th

numeral 1 indicates a suitable base, which maybe constructed of wood, metal, or celluloid, or other substance and which is pro-' 06 ings, similar parts are referred to by vided with a circular dial 2, as shown; The a dial 2 may be imprinted upon the face of the base 1i, or, it may consist of a separate plate, attached in any desired manner to the base 1. The dialconsists of a circular 'vided'into 360 eq'ual spaces of-subdivisi'ons. 3, which spaces. are

consecutively numbered from 0 to 360, start-1 ing from the arrow 4,- Pivotedconcentrically with the dial, 2 at. the pivot point. 5, is a circular dial 6 capable of rotation with respect to the dial 2. The dial 6 is rovided with a circular central space 7 which may be utilized for suitable legends orfoi' printed matter which will explain to the operator the manner of using the device. The circular segment of the dial 6 located between the circular portion 7 and the outer periphery of the dial is divided into twelve equal sectors 8, in which the names of the twelve months of the year are successively. imprinted. Each of the sectors 8, at the outer periphery thereof, is divided into thirty equal spaces or subdivisions 9, which are numbered consecutively from 1 to 30, the numbering being in the same direction as the numbering of the spaces on the dial 2. By my system of providing uniformly thirty spaces for each month, making 360 spaces for the entire year, extreme simplicity of construction of the device is obtained, since it is possible to divide the dial 6 into twelve sectors'of exactly the same size, and

each sector, which correspondsto a month is divided-into thirty equal spaces, reducingthe amount of geometrical calculation necessary for the provision of the spaceson the 4 dials. It is tobe understood, however, that 35 a dial 6 is rotated until the space No. or

56 "leaving 290, which is the'exact number of now proceed to describe.

an exact computation ofthe number of days which elapse between any two dates cannot, by this system, be correctly arrived at without the use of certain indicia which are placed on certain of the sectors 8 which correspond to the various months, WhlCh I W11] In each of thesectors 8 which correspond to a month having 31 days, I place an indieating mark of some sultable form, which in the drawings is shown in the form of a star 10; in practice the stars 10 placed in the sectors correspond to the months p of January, March, May, July, August, October, and December will be colored red. It

X "will be obvious, that in making a computation, by the manner hereinafter described, it will be necessary to add one to the number which the operator. will obtain from the dial 2 for each red star passed. In the sector which corresponds to the month of February, a star or other suitable indication 11 is placed,,and this star will be colored differently from the stars 10; in practice it will have a green color. As the month of.

February normally has two days less' than the number of spaces provided for each of the sectors 8, it will be necessary to subtract two from a computation arrived at in the manner hereinafter described, should the green star be passed;

In operating the device, the procedure would be as follows: Suppose, for example, it is desired to ascertain the number of days from January 5th to October 22nd. The

the January sector is opposite the arrow 4, which corresponds to 0 on the dial 2. With the two dials in this relative position, it will be seen that the number on the dial 2 which is opposite the space 22 of the October sector, is 287. In reckoning. 30 days to a month, as is often done when computing interest, the number 287 willbe the desired number, without any further corrections. To figure the exact number of days, the abovr procedure will be .followed, subject however to the following considerations. It will be seen that between the date January 5th and October 22nd, that five red stars will be found in the sectors, there being five months included which have 31 days. Add 5 to 287,292 is obtained, and as the green star is also passed in the period specified, two will be-subtracted from the above number,

days desired, except'in the case of leap year. Wh it is deslred to compute the number of diiiys between a date in advance of February of a leap year and a date later than the same, instead of subtracting two from the product arrived at by adding one for each red star, one. will be subtracted, since February of leap year has 29- days, one less than the number of spaces provided on each sector.

From the foregoing description it will be seen that I have provided'an extremely simple and convenient device, by which, with a little'practice, it will be an easy matter to make a quick computation of the number of days elapsing between any two dates.

The device does not possess any parts which are liable to get out of order, and b virtue of the system which I have em loye :may be constructed without diflicu t geometrical calculations.

-Having thus described the invention,

what is claimed as new is:

Y "1. A calculator device, consisting of con centric circular dials, sa1d dials be ng rotatable with respect to each other one of said dials being divided at its periphery into 360 equal parts or subdivisions which are numbered from 0 to 360, said dial having a suitable indication at the zero mark of said subdivisions, and the other of said dials being divided. into twelve equal sectors, which represent successively the months, each of said sectors being divided into 30 equal parts or subdivisions, numbered consecutively from 1 to 30 to indicate the days of the months, the said sectors which corre- J spond to the months having 31 days being each provided with a suitable indication to indicate to the operator that one is to be added for each of said indications which occurs between two specified dates on said second named dial, and the sector which corresponds to February being provided with a suitable indication which may be distinguished from the indications on the other sectors, to indicate that one is to besubtracted when the said indication occurs be:

tween two specified dates for leap year, and that two is to be subtracted for the normal years.

2. A calculator device, consisting of a fixed circular dial, said dial being divided at its periphery into 360 equal parts or subthe month, the said sectors which correspond to the months having 31 days being each provided with a suitable colored indication to indicate to the operator that one is to be added for each of said indications which occurs between two specified dates on said second named dial, and the sector which corresponds to February being provided with an indication having a color to con- In testimony whereof I afi'ix my signature tra'st with that of the indications (E1 the in presence of two witnesses; other sectors in order to indicate to t e op- I erator that bne is to be subtracted when MAUI) LOWRY R the said indication occurs between two specie Witnesses: I

fied dates for leap year, and that twolis OTTO F. PETERsoN,

to be subtracted for the normal years. AMY FoUoH. 

